Pregnant rabbits will be injected with alloxan on the 5th gestational day in order to study the chronic effects of varying degrees of diabetes mellitus on maternal, fetal and neonatal adrenal glucocorticoid production. At two day intervals beginning on the 25th day of gestation and the postpartum period maternal and fetal or neonatal adrenals will be collected and incubated in Krebs-Ringer Bicarbonate medium containing ACTH, Insulin, ACTH plus Insulin or no hormone. Cortisol and corticosterone production will be quantitated by radioimmunoassay. The degree of severity of diabetes will be determined by the sustained rise in blood glucose above controls. Blood samples will be taken on days 7, 14, 21 and 28 of gestation and at two day intervals postpartum for quantitation of glucose, free fatty acids, cortisol and corticosterone. When the diabetes is severe, blood glucose greater than 300 mg/dl, the animals will be injected with maintenance doses of Protamine Zinc Insulin; since we have previously shown that most, but not all, animals abort when blood glucose levels are above this level. The results will be compared to uninjected controls treated in the same manner as the injected animals.